British expats Spain EU
British expats watch the royal wedding of Prince William and Catherine Middleton on TV, on April 29, 2011 in Benalmadena, SpainDaniel Perez/Getty Images

The debate about whether the UK should stay a member of the European Union (EU) has almost entirely been about those living on the British Isles rather than elsewhere. This is probably because the EU's free movement policy and the strength of the British economy means more people enter from Europe than leave for the continent.

But a lot of Britons do take advantage of free movement to live elsewhere in the EU; they are sipping wine in the south of France, sipping wine in the Italian hills, sipping wine on the Spanish coast... In fact, there are 1.26 million UK citizens living outside the UK in the EU's other 27 member states. Excluding the UK, that equates to 0.3% of the EU's population.

Perhaps unsurprisingly, the UK's neighbour and former colony, Ireland, has the highest UK-born portion of its population of any EU member state, at 5.5% of the total. In nominal terms, that is 253,605 Britons -- which is not the highest by this reading. Spain, with its sun-tanned army of retired British expats, has the largest nominal population. There are 381,025 UK-born citizens, though this only accounts for 0.8% of the Spanish population.

And Estonia has the smallest UK-born population, both in nominal and portion terms -- 54 people, or 0.0004%. All of this was discovered by using data from the UN Department of Economic and Social Affairs (the most recent of which is for 2013), the ONS, and the World Bank.

As the EU referendum debate heats up, here is an infographic from IBTimes UK looking at the UK-born populations in EU member states, both as a proportion of the total national population and the nominal figure.

EU UK populations
The UK-born population of all other EU member states, by percentage portion of the national population and the nominal figureIBT/Luis Ouriach